https://jhsgh.github.io/storymap/
https://github.com/jhsgh/storymap
https://docs.google.com/spreadsheets/d/12GRaDtQJwPyjIQjPgB1L-z9jgGBkkywESuWv8njgbEQ/edit#gid=0
See step-by-step tutorial in Hands-On Data Visualization https://datavizforall.org/leaflet-storymaps-with-google-sheets.html